This is really nice! The music sets such a perfect chill mood, and while I realize this was a game jam game, I really wanted to be able to play more levels! Just as I got addicted to it, I reached the end.
The "fitting inside/together" aspect make this more interesting to me than something like Unpacking. I guess it's a sort of light puzzle element that makes it fun and addicting, but doesn't upset the chill vibe.
I hope you consider expanding this into a larger game of some sort. Love the little details too, like the names of things. And as Tahnan said, the questions the details bring up. Feels like there could be a story told through them if more levels were added. :)
I hope this does well in LD57. It deserves to!